compilation of the Twitter Bootstrap LESS files failes

The compilation of the Twitter Bootstrap LESS files failes with Bootstrap 
versions greater than 2.0.0. The exception is:

0    ERROR RhinoScriptBuilder   - JavaScriptException occured: [object Object] 
(run.js#7)
1    WARN LessCssProcessor     - Exception while applying LessCssProcessor 
processor on the  resource, no processing applied...
ro.isdc.wro.WroRuntimeException: Could not execute the script because: 
{"type":"Parse","message":"Syntax Error on line 
1309","index":100728.0,"filename":null,"line":1309.0,"column":6.0,"extract":["  
  .spanX (@index) when (@index > 0) {","      (~\".span@{index}\") { 
.span(@index); }","      .spanX(@index - 1);"]}
    at ro.isdc.wro.extensions.processor.support.less.LessCss.less(LessCss.java:87)

The line is contained in the file mixins.less of Bootstrap. I've tried it with 
the wro4j Maven plugin 1.4.4, it failed with Bootstrap 2.0.1 and 2.0.2, it 
succeded with 2.0.0.

Original issue reported on code.google.com by alex.obj...@gmail.com on 17 Mar 2012 at 7:23

Merged into: #397

changcheng / wro4j

compilation of the Twitter Bootstrap LESS files failes #396